“…Key and well-characterized cytokines, including IL-1a, IL-1b, TNF-a, IL-4, IL-6, IL-8, and IL-10, are highly expressed by structural cells from pulp tissue, such as odontoblasts, fibroblasts and mesenchymal stem cells, along with immune cells, when they are exposed to bacterial and dental materials components. [24][25][26][27][28] These molecules play regulatory functions for lymphocytes, macrophages, and neutrophils, activating the inflammatory cascade, 29,30 which may result in release of proteolytic enzymes, such as metalloproteinases, with the consequent disruption of extracellular matrix components. 31,32 Prostaglandin E 2 , synthesized by COX-2 gene is also a major pro-inflammatory mediator, which is known to accelerate inflammation and injury in several tissues, including the dental pulp.…”